Background: Zoletil has been used at different dose rates with or without preanaesthetics through intramuscular or intravenous routes in canine patients with varying results in other countries. The doses recommended by the manufacturer as well as researchers and the observations on various clinico-physiological and hemodynamic parameters are also highly variable. Keeping these points in mind, the present study was conducted to study anesthetic/sedative effects of intramuscular administration of Zoletil (20 mg/kg)&nbsp; and also to study the effect of glycopyrrolate (0.005 mg/kg)-xylazine (0.5 mg/kg) supplementation on Zoletil (10 mg/kg)-induced total intramuscular anesthesia in dogs.&nbsp; 
 
Methods: Fourteen canine patients were divided into two groups, viz., A and B, with seven animals in each group.In group A, Zoletil (tiletamine-zolazepam) at the dose rate of 20 mg/kg body weight was administered intramuscularly as an anaesthetic. In group B, preanesthetic glycopyrrolate at 0.005 mg/kg body weight was administered intramuscularly. After 15 minutes, xylazine at 0.5 mg/kg body weight was administered intramuscularly. After 15 minutes of preanesthetic administration in the B group, anaesthesia was induced intramuscularly with tiletamine-zolazepam @ 10 mg/kg body weight.&nbsp; 
 
Result: Zoletil (Tiletamine-zolazepam, 20 mg/kg IM) (group A) is only recommended for non-surgical/diagnostic (viz. Gastro-intestinal endoscopy)/minor surgical procedures in uncooperative dogs. An intramuscular anaesthetic protocol using glycopyrrolate (0.005 mg/kg)-xylazine (0.5 mg/kg) - Zoletil (10 mg/kg IM) (group B) is recommended for major surgical procedures of long duration. Neither the anaesthetic protocol produced any serious deleterious effect on hemato-biochemical and hemodynamic parameters; hence both protocols can be used safely in dogs as per the requirements of the procedure.

Effect of Glycopyrrolate-xylazine Supplementation on Zoletil-induced Total Intramuscular Anaesthesia in Dogs